This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The Ebola virus causes severe hemorrhagic fever with 50-90% lethality. The viral nucleocapsid and polymerase complex are key contributors to the extraordinary pathogenesis of this virus as the component proteins suppress innate immune signalling while replicating the negative strand RNA genome at a tremendous rate. We are pursuing x-ray crystallographic studies on the key viral proteins VP35, VP24, NP, and L. These proteins self-assemble into helical tubes (60 nm x 700-2000 nm) that determine the filamentous viral morphology. We are interested in using EM in order to verify morphology of our protein complexes and perhaps to obtain low resolution phasing information. Further studies by cryoEM might be possible, especially for large complexes refractory to crystallization.